Lusus
| site = | pronounce = Lusis | adjective = Lusian | dino = Cijij | planet_numbers = P106 HD 70642 P1 Puppis P1 Malus P6 2003 P14 2003 Pup-1 2003 Mal-3 | star_designations = PS 84 b P1 Puppis b P6 Mali b 40952 b 304 b 199126 b | star = HD 70642 | constellation = | lactoph = Malus | ra = 125.3672222° | dec = −39.7054074° | distance = 28.064 91.532 0.86596 5.7888 | planets = Lusitania (hypothetical) Iberia (hypothetical) Fulgora (hypothetical) Oscilla (hypothetical) | semimajor = 3.366918 503.6838 312.9783 Mmi 16.323279 μpc 28.00180 862.20 stellar radii | semiminor = 3.365013 AU 503.3988 Gm 312.8012 Mmi 16.314044 μpc 27.98596 lmin 861.71 stellar radii | periastron = 3.253676 AU 486.7430 Gm 302.4517 Mmi 15.774267 μpc 27.06000 lmin 833.20 stellar radii | apastron = 3.480160 AU 520.6245 Gm 323.5049 Mmi 16.872291 μpc 28.94361 lmin 891.20 stellar radii | eccentricity = 0.0336337 | orbital_circ = 21.15060 AU 3164.084 Gm 1966.094 Mmi 102.54099 μpc 175.9042 lmin | orbital_area = 35.59337 AU2 796562.7 Gm2 307561.95 Mmi2 836.60198 μpc2 2461.932 lmin2 | orbital_period = 2230.734933 6.10741939 192.73544982 11367.36 Lusian rotations | avg_speed = 16.47 10.24 3.46 AU/yr 0.534 ppc/s 54.9 lμs/s | max_speed = 16.75 km/s 10.41 mi/s 3.52 AU/yr 0.543 ppc/s 55.9 lμs/s | min_speed = 16.19 km/s 10.06 mi/s 3.40 AU/yr 0.525 ppc/s 54.0 lμs/s | orbit_direction = | inclination = 138.259° to 1.11° to star’s equator 4.10° to | arg_peri = 277.210° | node = 344.334° | long_peri = 621.544° | separation = 119.974 | moons = 101 | rings = 32 | mean_star_size = 0.134° (8.0') | max_star_size = 0.138° (8.3') | min_star_size = 0.129° (7.8') | mean_star_magnitude = −23.997 | max_star_magnitude = −24.072 | min_star_magnitude = −23.926 | mean_radius = 8.8957 0.8189 56.675 35.216 kmi 1.7488 npc 11.343 lj | equatoral_radius = 9.2483 R⊕ 0.8514 RJ 58.921 Mm 36.612 kmi 1.8181 npc | polar_radius = 8.5431 R⊕ 0.7865 RJ 54.428 Mm 33.820 kmi 1.6795 npc 10.893 lj | mean_circ = 356.097 Mm 221.268 kmi 10.9880 npc 71.269 lj | equatoral_circ = 370.211 Mm 221.268 kmi 11.4235 npc 74.093 lj | polar_circ = 341.982 Mm 212.498 kmi 10.5525 npc 68.444 lj | surface_area = 82.205 S⊕ 0.6967 SJ 41930 Mm2 16190 kmi2 39.92 npc2 1680 lj2 | volume = 703.70 V⊕ 0.5701 VJ 791500 Mm3 189900 kmi3 23.25 npc3 158400 lj3 | oblateness = 0.07927 | aspect_ratio = 0.92375 | mass = 939.9 2.9572 5.6145 Wg 6.1888 Xt | recip_mass = 362.5 | classification = Super-Jupiter | density = 6.881 g/cm3 | gravity = 10.738 105.24 m/s2 345.26 ft/s2 3.2473 fpc/s2 373.75 lns/s2 | gm = 374.652 × 106 km3/s2 | escape_v = 113.11 km/s 70.28 mi/s 3.666 ppc/s 377.3 lμs/s | hill_radius = 128.06 LU 49.23 Gm 1519 npc 164.21 869 planetary radii | axial_tilt = 79.64° | np_ra = 105.02500° | np_dec = −41.71889° | rot_period = 4.70977 0.196240 16.9552 | rot_velocity = 21.696 km/s 13.481 mi/s 78105 kph 48532 mph 703.11 fpc/s 72.37 lns/s | rot_direction = | cloudtop_temp = 122 (−151 , −240 , 220 ) | c_peri_temp = 124 K (−149°C, −236°F, 224°R) | c_apo_temp = 120 K (−153°C, −243°F, 216°R) | 1bar_temp = 233 K (−40°C, −40°F, 420°R) | irradiance = 72 (0.052 ) | peri_irradiance = 77 W/m2 (0.056 I⊕) | apo_irradiance = 67 W/m2 (0.049 I⊕) | albedo = 0.458 ( ) 0.560 ( ) | peri_albedo = 0.461 ( ) 0.563 ( ) | apo_albedo = 0.451 ( ) 0.557 ( ) | property = Ammonia cloud jovian | scale_height = 8.7 (5.4 , 26.8 ppc, 29.2 ) | 1bar_density = 0.52 g/m3 | molar_mass = 2.21 g/mol | composition = 90.551% (H2) 9.377% (He) 633 ppm (NH4) 41 ppm (CH4) 12 ppm (H2O) 983 ppb (HD) 330 ppb (C2H6) 20 ppb (Ne) 840 ppt (H2S) 320 ppt (PH3) 19 ppt (C6H6) Aerosols: (NH3) (H2O) (NH4SH) | dipole_strength = 2028 (20.28 ) | magnetic_moment = 5.21 × 1021 T•m3 | dipole_tilt = 8.59° | long_tilt = 177.01° | magnetic_offset = 0.38 Rp (0.056 LU, 0.021 Gm, 0.66 npc, 0.071 ls) | magnetopause = 86.4 Rp (12.74 LU, 4.90 Gm, 151.2 npc, 16.33 ls) | bow_shock = 108.2 Rp (15.96 LU, 6.13 Gm, 189.2 npc, 20.46 ls) | tail_length = 21102.7 Rp (3111.33 LU, 1196.0 Gm, 36904.2 npc, 3989.46 ls) | ions = H2O+, H3O+, HO3+, H+, O+, NH4+ | loading_rate = 3811 kg/s | plasma_density = 8650 cm−3 | particle_energy = 532 }} Lusus (often referred as HD 70642 b) is an which orbits the HD 70642, 92 s or 28 s from in the , which is located in the lactoph Malus. Lusus is a with ammonia clouds like , although it is three times more massive than Jupiter and the size is smaller than Jupiter, due to its , making this planet denser than Earth, even though it is a . is named after the of wine and divine madness. Discovery Lusus was discovered on July 3, 2003 by a team of astronomers led by Carter. The team used the mounted on to study this star to look for any evidence of planets. The team looked at radial velocity data of HD 70642 and found the periodic graph consistent with a 6-year period with a 2.0 MJup. The semimajor axis of this planet wasn’t directly determined, but it was calculated based on its period and the mass of the parent star. The semimajor axis of this planet was determined to be 3.3 AU and has a low eccentricity of 0.1. Chronology and designations Lusus is the 98th exoplanet discovered since Dannaus ( ) was discovered in July 1988. Lusus has a planet number 106. Lusus is the first planet discovered in the HD 70642 system, hence its designation HD 70642 b (although a is not used because the parent star uses this letter to reduce confusion). Lusus is the first planet discovered in and it is the sixth planet discovered in Malus. It is the 14th planet discovered in 2003, 1st in Puppis and 3rd in Malus. For all of the chronologies and planet number, planetary candidates that are speculated to be s are not counted. Typically for planets, the useful designations are BF, Bayer, Flamsteed, PS, designations of stars that have planets, HD, HIP, HR, Gliese and GJ, and SAO, although most planets don’t have BF, Bayer, Flamsteed, HR, and Gliese and GJ. Lusus has designations PS 184 b, P1 Puppis b, P6 Mali b, HD 70642 b, HIP 40952 b, Gliese 304 b, and SAO 199126 b. Orbit and rotation Lusus takes 6.1 years to orbit the star at the average distance of 3.37 AU. Unlike most long-period planets known, Lusus orbits in a circular path with an eccentricity of 0.034, which is more circular than Jupiter (0.049), but more eccentric than Earth (0.017). The orbital distance varies by 0.23 AU throughout its orbit. The direction of Lusus’s orbit is the same as the parent star's rotation, like all planets in our solar system do. The planet moves in an average speed of 16.5 km/s. The actual inclination of this planet is unknown, but it is speculated to be 138° (1.11° to star’s equator). The argument of periastron is 277° and the longitude of ascending node is 344°, corresponding to the longitude of periastron 622°. Lusus takes 4 hours and 43 minutes to rotate once on its axis, which is over twice as short as Jupiter, the shortest rotation period of any planets in our solar system. The rotation velocity is 21.7 km/s or 13.5 mi/s, which is faster than Jupiter. Lusus rotates the same direction is its orbit and rotation of the star. Its year on Lusus lasts 11370 Lusus days. Observing the parent star When viewing HD 70642 from one of its moons, that sun is 12.5 times fainter than the Sun as seen from Earth, but 2.2 times brighter than the Sun as seen from Jupiter. So the apparent magnitude of HD 70642 as seen from Lusus is −24.00. The of HD 70642 as seen from Lusus is 0.134°, which is 1/4 the angular diameter of the full moon and sun as seen from Earth, due to in fact Lusus orbits further away from the star than Earth to the Sun and HD 70642 itself is 19% smaller than our Sun. Physical characteristics Using the speculated inclination, its speculated for Lusus is 2.95 MJ or 6.19 xentatons. This planet is classified as Super-Jupiter since the planet’s mass is between 2 and 13 times that of Jupiter. Despite its mass, Lusus is smaller than Jupiter, about the size of . is the cause why this planet is smaller while more massive than Jupiter. Since it is a gas giant, it has the ability to contract by gravity. Since its formation 3.9 billion years ago, Lusus was three times larger than Jupiter. Lusus is shrinking by 8 cm/yr. Lusus has density 6.881 g/cm3, which is 5.2 times denser than Jupiter and 25% denser than Earth. Lusus has gravitational force 10.7 times stronger than Earth’s and 4.2 times stronger than Jupiter’s. If you weigh 150 lbs on Earth, you would weigh 1611 lbs or 4/5 ton on Lusus. Structure Composition Lusus’s atmosphere composes of 99.9% and . Lusus has similar composition to Jupiter. Lusus contain trace amounts of , , , , , , , , and . The ices in the atmosphere are , , and . Interior Like Jupiter, beneath Lusus’s outer envelope, it has a mantle of and due to its tremendous pressure. Below that layer lies liquid where hydrogen can conduct electricity. At the center lies a small core of rock and metal with a mass 18 Earth masses, roughly 1.9% the total mass of the planet. Atmosphere The clouds on Lusus composed mainly of ammonia like it is found on Jupiter and Saturn. The mean temperature of the cloudtop is 122 K (−151°C or −240°F). At 1-bar layer, the temperature is 233 K (−40°C or −40°F), near the melting point of . It may have cloud bands similar to Jupiter. The winds on the planet move at a speed of 800 mph (1300 kph). There could even be “ ” on Lusus. The number of s and s could be slightly more than Jupiter. Magnetosphere This planet has a powerful that can block radiation coming off from HD 70642 and causes e at the poles. The magnetic field of Lusus is 4.74 times more powerful than and 66 times more powerful than . The mass loading rate is 3.8 metric tons per second and the intensity of the energy 532 MeV. Moons and rings Lusus has 101 moons that are larger than 1 km across. A lot of those moons are icy, while some are rocky and cratered. Some moons have subsurface oceans like , some volcanic like caused by strong tidal forces of the parent planet, and some have hazy atmospheres like . The largest moon has diameter of 3,973 miles (6,394 kilometers) and has mass 4.39 es, which is larger and more massive than , the largest moon in the , but slightly smaller and less massive than . That moon has a thick atmosphere. The Io-like moon has diameter of 2,674 miles (4,304 kilometers) and has mass 1.77 ML. The Europa-like moon has diameter of 3,386 miles (5,449 kilometers) and has mass 1.16 ML. There is a slate moon with sulfur deposits that has a diameter of 1,933 miles (3,110 kilometers) and has mass 0.77 ML. There are three moons that are larger than 2000 miles, seven are between 1000-2000 miles, 36 are between 100-1000 miles, and 55 are less than 100 miles across. The rings around Lusus are even more tenuous than as it is made of almost entirely of dust. There are 32 ultra-narrow, ultra-thin, and ultra-dark rings. Future studies The method will use to study Lusus might be . It is not likely that Lusus will transit its star. The probability that this planet will transit HD 70642 will be a slim 0.37% chance. The method of direct imaging might be done using space telescopes like or and will be equipped with spectrometer and astroseismometer. Using direct imaging, it can determine what Lusus actually looks like. Lusus should be the important target for future studies because it is a long-period Jupiter-like planet. Determining the inclination using from is important for determining its true mass and determine whether it is a planet or a brown dwarf. However it is very likely to be a planet because its minimum mass is 1.97 MJup and the inclination must be at least 171.29° or at most 8.71° in order for true mass to be at least 13.00 MJup, the borderline between planets and brown dwarfs. Determining the size of this planet is also important. After determining its size, density and gravity will be calculated. Using the density of the planet, astronomers can probe the interior and determine the mass and size of the core. Astronomers will also study the mantle and its temperature of the core using . The size of Lusus at 0.82 MJup is small to being a 2.95 MJup at the age of 3.9 billion years. It could actually be bigger, about the size of Jupiter. It should also determine its temperature and chemicals in the atmosphere using spectroscopy. Another important property is determining its rotation rate, in which the rotation period can be determine using the circumference of the planet and rotation rate. The space telescope should also find moons and even rings around the planet. Finding moons could be done using direct imaging, transit across its host planet, and studying the wobble of the planet. By using all three methods, it will determine its mass, size (in which its density and gravity can be determined), surface temperature, atmospheric composition, surface textures, appearance, orbital distance from the planet, orbital period, eccentricity, and rotation period of the moons. Category:Ammonia cloud jovians Category:Articles Category:Extrasolar planets Category:Super-Jupiters